1. Field of the Invention
The invention relates to a method for a channel scanning device and method thereof, and more particularly, to a channel scanning device for quickly scanning channels and method thereof.
2. Description of the Prior Art
When proceeding with channel-searching operations related to the wireless/wiring TV broadcasting, users can make use of a tuner to determine a predetermined channel first and then utilize the receiver to receive video/audio signals transmitted via the channel. Therefore, the users require the predetermined channel for transmitting the video/audio signals in advance or adjust the tuner by hand to receive the video/audio signals. When the video/audio signals are transmitted by the satellite, the carrier position of the channel, the symbol rate, and the encoding operation may occasionally vary in order to improve the performance and efficiency of the satellite; that is, the users have to refresh the related parameters of the channels, which are inputted into the tuner in advance, so that the tuner can be used to check whether it holds the video/audio signal. Otherwise, the receiver has to predict whether the video/audio signal exists according to various carrier positions and symbol rates in order to search the channel. According to above-mentioned prior-art technique, the receiver is likely to spend too much time to achieve the channel-searching operations.
Since the requirements towards the digital TV broadcasting will significantly increase in the near future, the above-mentioned problem related to the variation of characteristics of the channel may be aggravated when the video/audio signal is transmitted by the satellite. Therefore, the rate of the channel-searching operation may become the bottleneck of the performance of the receiver.